context_menu.rs

  1use gpui::{
  2    anyhow,
  3    elements::*,
  4    geometry::vector::Vector2F,
  5    impl_internal_actions,
  6    keymap_matcher::KeymapContext,
  7    platform::{CursorStyle, MouseButton},
  8    Action, AnyViewHandle, AppContext, Axis, Entity, MouseState, SizeConstraint, Subscription,
  9    View, ViewContext,
 10};
 11use menu::*;
 12use settings::Settings;
 13use std::{any::TypeId, borrow::Cow, sync::Arc, time::Duration};
 14
 15#[derive(Copy, Clone, PartialEq)]
 16struct Clicked;
 17
 18impl_internal_actions!(context_menu, [Clicked]);
 19
 20pub fn init(cx: &mut AppContext) {
 21    cx.add_action(ContextMenu::select_first);
 22    cx.add_action(ContextMenu::select_last);
 23    cx.add_action(ContextMenu::select_next);
 24    cx.add_action(ContextMenu::select_prev);
 25    cx.add_action(ContextMenu::clicked);
 26    cx.add_action(ContextMenu::confirm);
 27    cx.add_action(ContextMenu::cancel);
 28}
 29
 30pub type StaticItem = Box<dyn Fn(&mut AppContext) -> AnyElement<ContextMenu>>;
 31
 32type ContextMenuItemBuilder =
 33    Box<dyn Fn(&mut MouseState, &theme::ContextMenuItem) -> AnyElement<ContextMenu>>;
 34
 35pub enum ContextMenuItemLabel {
 36    String(Cow<'static, str>),
 37    Element(ContextMenuItemBuilder),
 38}
 39
 40impl From<Cow<'static, str>> for ContextMenuItemLabel {
 41    fn from(s: Cow<'static, str>) -> Self {
 42        Self::String(s)
 43    }
 44}
 45
 46impl From<&'static str> for ContextMenuItemLabel {
 47    fn from(s: &'static str) -> Self {
 48        Self::String(s.into())
 49    }
 50}
 51
 52impl From<String> for ContextMenuItemLabel {
 53    fn from(s: String) -> Self {
 54        Self::String(s.into())
 55    }
 56}
 57
 58impl<T> From<T> for ContextMenuItemLabel
 59where
 60    T: 'static + Fn(&mut MouseState, &theme::ContextMenuItem) -> AnyElement<ContextMenu>,
 61{
 62    fn from(f: T) -> Self {
 63        Self::Element(Box::new(f))
 64    }
 65}
 66
 67pub enum ContextMenuItemAction {
 68    Action(Box<dyn Action>),
 69    Handler(Arc<dyn Fn(&mut ViewContext<ContextMenu>)>),
 70}
 71
 72impl Clone for ContextMenuItemAction {
 73    fn clone(&self) -> Self {
 74        match self {
 75            Self::Action(action) => Self::Action(action.boxed_clone()),
 76            Self::Handler(handler) => Self::Handler(handler.clone()),
 77        }
 78    }
 79}
 80
 81pub enum ContextMenuItem {
 82    Item {
 83        label: ContextMenuItemLabel,
 84        action: ContextMenuItemAction,
 85    },
 86    Static(StaticItem),
 87    Separator,
 88}
 89
 90impl ContextMenuItem {
 91    pub fn action(label: impl Into<ContextMenuItemLabel>, action: impl 'static + Action) -> Self {
 92        Self::Item {
 93            label: label.into(),
 94            action: ContextMenuItemAction::Action(Box::new(action)),
 95        }
 96    }
 97
 98    pub fn handler(
 99        label: impl Into<ContextMenuItemLabel>,
100        handler: impl 'static + Fn(&mut ViewContext<ContextMenu>),
101    ) -> Self {
102        Self::Item {
103            label: label.into(),
104            action: ContextMenuItemAction::Handler(Arc::new(handler)),
105        }
106    }
107
108    pub fn separator() -> Self {
109        Self::Separator
110    }
111
112    fn is_action(&self) -> bool {
113        matches!(self, Self::Item { .. })
114    }
115
116    fn action_id(&self) -> Option<TypeId> {
117        match self {
118            ContextMenuItem::Item { action, .. } => match action {
119                ContextMenuItemAction::Action(action) => Some(action.id()),
120                ContextMenuItemAction::Handler(_) => None,
121            },
122            ContextMenuItem::Static(..) | ContextMenuItem::Separator => None,
123        }
124    }
125}
126
127pub struct ContextMenu {
128    show_count: usize,
129    anchor_position: Vector2F,
130    anchor_corner: AnchorCorner,
131    position_mode: OverlayPositionMode,
132    items: Vec<ContextMenuItem>,
133    selected_index: Option<usize>,
134    visible: bool,
135    previously_focused_view_id: Option<usize>,
136    clicked: bool,
137    parent_view_id: usize,
138    _actions_observation: Subscription,
139}
140
141impl Entity for ContextMenu {
142    type Event = ();
143}
144
145impl View for ContextMenu {
146    fn ui_name() -> &'static str {
147        "ContextMenu"
148    }
149
150    fn keymap_context(&self, _: &AppContext) -> KeymapContext {
151        let mut cx = Self::default_keymap_context();
152        cx.add_identifier("menu");
153        cx
154    }
155
156    fn render(&mut self, cx: &mut ViewContext<Self>) -> AnyElement<Self> {
157        if !self.visible {
158            return Empty::new().into_any();
159        }
160
161        // Render the menu once at minimum width.
162        let mut collapsed_menu = self.render_menu_for_measurement(cx);
163        let expanded_menu =
164            self.render_menu(cx)
165                .constrained()
166                .dynamically(move |constraint, view, cx| {
167                    SizeConstraint::strict_along(
168                        Axis::Horizontal,
169                        collapsed_menu.layout(constraint, view, cx).0.x(),
170                    )
171                });
172
173        Overlay::new(expanded_menu)
174            .with_hoverable(true)
175            .with_fit_mode(OverlayFitMode::SnapToWindow)
176            .with_anchor_position(self.anchor_position)
177            .with_anchor_corner(self.anchor_corner)
178            .with_position_mode(self.position_mode)
179            .into_any()
180    }
181
182    fn focus_out(&mut self, _: AnyViewHandle, cx: &mut ViewContext<Self>) {
183        self.reset(cx);
184    }
185}
186
187impl ContextMenu {
188    pub fn new(cx: &mut ViewContext<Self>) -> Self {
189        let parent_view_id = cx.parent().unwrap();
190
191        Self {
192            show_count: 0,
193            anchor_position: Default::default(),
194            anchor_corner: AnchorCorner::TopLeft,
195            position_mode: OverlayPositionMode::Window,
196            items: Default::default(),
197            selected_index: Default::default(),
198            visible: Default::default(),
199            previously_focused_view_id: Default::default(),
200            clicked: false,
201            parent_view_id,
202            _actions_observation: cx.observe_actions(Self::action_dispatched),
203        }
204    }
205
206    pub fn visible(&self) -> bool {
207        self.visible
208    }
209
210    fn action_dispatched(&mut self, action_id: TypeId, cx: &mut ViewContext<Self>) {
211        if let Some(ix) = self
212            .items
213            .iter()
214            .position(|item| item.action_id() == Some(action_id))
215        {
216            if self.clicked {
217                self.cancel(&Default::default(), cx);
218            } else {
219                self.selected_index = Some(ix);
220                cx.notify();
221                cx.spawn(|this, mut cx| async move {
222                    cx.background().timer(Duration::from_millis(50)).await;
223                    this.update(&mut cx, |this, cx| this.cancel(&Default::default(), cx))?;
224                    anyhow::Ok(())
225                })
226                .detach_and_log_err(cx);
227            }
228        }
229    }
230
231    fn clicked(&mut self, _: &Clicked, _: &mut ViewContext<Self>) {
232        self.clicked = true;
233    }
234
235    fn confirm(&mut self, _: &Confirm, cx: &mut ViewContext<Self>) {
236        if let Some(ix) = self.selected_index {
237            if let Some(ContextMenuItem::Item { action, .. }) = self.items.get(ix) {
238                match action {
239                    ContextMenuItemAction::Action(action) => {
240                        let window_id = cx.window_id();
241                        cx.dispatch_any_action_at(
242                            window_id,
243                            self.parent_view_id,
244                            action.boxed_clone(),
245                        );
246                    }
247                    ContextMenuItemAction::Handler(handler) => handler(cx),
248                }
249                self.reset(cx);
250            }
251        }
252    }
253
254    fn cancel(&mut self, _: &Cancel, cx: &mut ViewContext<Self>) {
255        self.reset(cx);
256        let show_count = self.show_count;
257        cx.defer(move |this, cx| {
258            if cx.handle().is_focused(cx) && this.show_count == show_count {
259                let window_id = cx.window_id();
260                (**cx).focus(window_id, this.previously_focused_view_id.take());
261            }
262        });
263    }
264
265    fn reset(&mut self, cx: &mut ViewContext<Self>) {
266        self.items.clear();
267        self.visible = false;
268        self.selected_index.take();
269        self.clicked = false;
270        cx.notify();
271    }
272
273    fn select_first(&mut self, _: &SelectFirst, cx: &mut ViewContext<Self>) {
274        self.selected_index = self.items.iter().position(|item| item.is_action());
275        cx.notify();
276    }
277
278    fn select_last(&mut self, _: &SelectLast, cx: &mut ViewContext<Self>) {
279        for (ix, item) in self.items.iter().enumerate().rev() {
280            if item.is_action() {
281                self.selected_index = Some(ix);
282                cx.notify();
283                break;
284            }
285        }
286    }
287
288    fn select_next(&mut self, _: &SelectNext, cx: &mut ViewContext<Self>) {
289        if let Some(ix) = self.selected_index {
290            for (ix, item) in self.items.iter().enumerate().skip(ix + 1) {
291                if item.is_action() {
292                    self.selected_index = Some(ix);
293                    cx.notify();
294                    break;
295                }
296            }
297        } else {
298            self.select_first(&Default::default(), cx);
299        }
300    }
301
302    fn select_prev(&mut self, _: &SelectPrev, cx: &mut ViewContext<Self>) {
303        if let Some(ix) = self.selected_index {
304            for (ix, item) in self.items.iter().enumerate().take(ix).rev() {
305                if item.is_action() {
306                    self.selected_index = Some(ix);
307                    cx.notify();
308                    break;
309                }
310            }
311        } else {
312            self.select_last(&Default::default(), cx);
313        }
314    }
315
316    pub fn show(
317        &mut self,
318        anchor_position: Vector2F,
319        anchor_corner: AnchorCorner,
320        items: Vec<ContextMenuItem>,
321        cx: &mut ViewContext<Self>,
322    ) {
323        let mut items = items.into_iter().peekable();
324        if items.peek().is_some() {
325            self.items = items.collect();
326            self.anchor_position = anchor_position;
327            self.anchor_corner = anchor_corner;
328            self.visible = true;
329            self.show_count += 1;
330            if !cx.is_self_focused() {
331                self.previously_focused_view_id = cx.focused_view_id();
332            }
333            cx.focus_self();
334        } else {
335            self.visible = false;
336        }
337        cx.notify();
338    }
339
340    pub fn set_position_mode(&mut self, mode: OverlayPositionMode) {
341        self.position_mode = mode;
342    }
343
344    fn render_menu_for_measurement(&self, cx: &mut ViewContext<Self>) -> impl Element<ContextMenu> {
345        let style = cx.global::<Settings>().theme.context_menu.clone();
346        Flex::row()
347            .with_child(
348                Flex::column().with_children(self.items.iter().enumerate().map(|(ix, item)| {
349                    match item {
350                        ContextMenuItem::Item { label, .. } => {
351                            let style = style.item.style_for(
352                                &mut Default::default(),
353                                Some(ix) == self.selected_index,
354                            );
355
356                            match label {
357                                ContextMenuItemLabel::String(label) => {
358                                    Label::new(label.to_string(), style.label.clone())
359                                        .contained()
360                                        .with_style(style.container)
361                                        .into_any()
362                                }
363                                ContextMenuItemLabel::Element(element) => {
364                                    element(&mut Default::default(), style)
365                                }
366                            }
367                        }
368
369                        ContextMenuItem::Static(f) => f(cx),
370
371                        ContextMenuItem::Separator => Empty::new()
372                            .collapsed()
373                            .contained()
374                            .with_style(style.separator)
375                            .constrained()
376                            .with_height(1.)
377                            .into_any(),
378                    }
379                })),
380            )
381            .with_child(
382                Flex::column()
383                    .with_children(self.items.iter().enumerate().map(|(ix, item)| {
384                        match item {
385                            ContextMenuItem::Item { action, .. } => {
386                                let style = style.item.style_for(
387                                    &mut Default::default(),
388                                    Some(ix) == self.selected_index,
389                                );
390
391                                match action {
392                                    ContextMenuItemAction::Action(action) => KeystrokeLabel::new(
393                                        self.parent_view_id,
394                                        action.boxed_clone(),
395                                        style.keystroke.container,
396                                        style.keystroke.text.clone(),
397                                    )
398                                    .into_any(),
399                                    ContextMenuItemAction::Handler(_) => Empty::new().into_any(),
400                                }
401                            }
402
403                            ContextMenuItem::Static(_) => Empty::new().into_any(),
404
405                            ContextMenuItem::Separator => Empty::new()
406                                .collapsed()
407                                .constrained()
408                                .with_height(1.)
409                                .contained()
410                                .with_style(style.separator)
411                                .into_any(),
412                        }
413                    }))
414                    .contained()
415                    .with_margin_left(style.keystroke_margin),
416            )
417            .contained()
418            .with_style(style.container)
419    }
420
421    fn render_menu(&self, cx: &mut ViewContext<Self>) -> impl Element<ContextMenu> {
422        enum Menu {}
423        enum MenuItem {}
424
425        let style = cx.global::<Settings>().theme.context_menu.clone();
426
427        MouseEventHandler::<Menu, ContextMenu>::new(0, cx, |_, cx| {
428            Flex::column()
429                .with_children(self.items.iter().enumerate().map(|(ix, item)| {
430                    match item {
431                        ContextMenuItem::Item { label, action } => {
432                            let action = action.clone();
433                            let view_id = self.parent_view_id;
434                            MouseEventHandler::<MenuItem, ContextMenu>::new(ix, cx, |state, _| {
435                                let style =
436                                    style.item.style_for(state, Some(ix) == self.selected_index);
437                                let keystroke = match &action {
438                                    ContextMenuItemAction::Action(action) => Some(
439                                        KeystrokeLabel::new(
440                                            view_id,
441                                            action.boxed_clone(),
442                                            style.keystroke.container,
443                                            style.keystroke.text.clone(),
444                                        )
445                                        .flex_float(),
446                                    ),
447                                    ContextMenuItemAction::Handler(_) => None,
448                                };
449
450                                Flex::row()
451                                    .with_child(match label {
452                                        ContextMenuItemLabel::String(label) => {
453                                            Label::new(label.clone(), style.label.clone())
454                                                .contained()
455                                                .into_any()
456                                        }
457                                        ContextMenuItemLabel::Element(element) => {
458                                            element(state, style)
459                                        }
460                                    })
461                                    .with_children(keystroke)
462                                    .contained()
463                                    .with_style(style.container)
464                            })
465                            .with_cursor_style(CursorStyle::PointingHand)
466                            .on_up(MouseButton::Left, |_, _, _| {}) // Capture these events
467                            .on_down(MouseButton::Left, |_, _, _| {}) // Capture these events
468                            .on_click(MouseButton::Left, move |_, _, cx| {
469                                let window_id = cx.window_id();
470                                cx.dispatch_action(Clicked);
471                                match &action {
472                                    ContextMenuItemAction::Action(action) => {
473                                        cx.dispatch_any_action_at(
474                                            window_id,
475                                            view_id,
476                                            action.boxed_clone(),
477                                        );
478                                    }
479                                    ContextMenuItemAction::Handler(handler) => handler(cx),
480                                }
481                            })
482                            .on_drag(MouseButton::Left, |_, _, _| {})
483                            .into_any()
484                        }
485
486                        ContextMenuItem::Static(f) => f(cx),
487
488                        ContextMenuItem::Separator => Empty::new()
489                            .constrained()
490                            .with_height(1.)
491                            .contained()
492                            .with_style(style.separator)
493                            .into_any(),
494                    }
495                }))
496                .contained()
497                .with_style(style.container)
498        })
499        .on_down_out(MouseButton::Left, |_, _, cx| cx.dispatch_action(Cancel))
500        .on_down_out(MouseButton::Right, |_, _, cx| cx.dispatch_action(Cancel))
501    }
502}